[INTERNAL] sap.m.ComboBox: qUnit test fixes
[INTERNAL] sap.m.ComboBox: qUnit test fixes

Change-Id: Ifeb512d13e036580531a9a02881c9170ca5be98b

nzamani/openui5,olirogers/openui5,olirogers/openui5,SAP/openui5,cschuff/openui5,nzamani/openui5,SAP/openui5,SQCLabs/openui5,olirogers/openui5,SQCLabs/openui5,nzamani/openui5,SAP/openui5,cschuff/openui5,SQCLabs/openui5,cschuff/openui5,SAP/openui5